EZ80F91MCU ZILOG [Zilog, Inc.], EZ80F91MCU Datasheet - Page 312
![no-image](/images/no-image-200.jpg)
EZ80F91MCU
Manufacturer Part Number
EZ80F91MCU
Description
eZ80Acclaim-TM Flash Microcontrollers
Manufacturer
ZILOG [Zilog, Inc.]
Datasheet
1.EZ80F91MCU.pdf
(396 pages)
- Current page: 312 of 396
- Download datasheet (5Mb)
Figure 59. ZDI Block Data Read Timing
PS019209-0504
ZDA
ZCL
Operation of the eZ80F91 Device during ZDI Break Points
Bus Requests During ZDI Debug Mode
ZDI Address
lsb of
ments with each Read. If the ZDI register address reaches the end of the Read
Only ZDI register address space (
illustrates the ZDI’s block Read timing.
If the ZDI forces the CPU to break, only the CPU suspends operation. The system
clock continues to operate and drive other peripherals. Those peripherals that can
operate autonomously from the CPU can continue to operate, if so enabled. For
example, the Watch-Dog Timer and Programmable Reload Timers continue to
count during a ZDI break point.
When using the ZDI interface, any Write or Read operations of peripheral regis-
ters in the I/O address space produces the same effect as Read or Write opera-
tions using the CPU. Because many register Read/Write operations exhibit
secondary effects, such as clearing flags or causing operations to commence, the
effects of the Read/Write operations during a ZDI break must be taken into con-
sideration.
The ZDI block on the eZ80F91 device allows an external device to take control of
the address and data bus while the eZ80F91 device is in DEBUG mode.
ZDI_BUSACK_EN causes ZDI to allow or prevent acknowledgement of bus
requests by external peripherals. The bus acknowledge only occurs at the end of
the current ZDI operation (indicated by a High during the single-bit byte separa-
tor). The default reset condition is for bus acknowledgement to be disabled. To
allow bus acknowledgement, the ZDI_BUSACK_EN must be written.
When an external bus request (BUSREQ pin asserted) is detected, ZDI waits until
completion of the current operation before responding. ZDI acknowledges the bus
request by asserting the bus acknowledge (BUSACK) signal. If the ZDI block is
A0
7
Read
8
Byte Separator
Single-Bit
0/1
9
of DATA
Byte 1
msb
D7
1
P R E L I M I N A R Y
D6
2
D5
3
20h
), the address stops incrementing. Figure 59
ZDI Data Bytes
D1
7
of DATA
Byte 1
D0
lsb
8
Byte Separator
Single-Bit
0/1
9
of DATA
Byte 2
msb
D7
Product Specification
1
ZiLOG Debug Interface
D6
2
eZ80F91 MCU
1
9
293
Related parts for EZ80F91MCU
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
![EZ80L920210ZCO](/images/manufacturer_photos/0/7/729/zilog_tmb.jpg)
Part Number:
Description:
KIT DEV EZ80 WEB SERVER
Manufacturer:
Zilog
Datasheet:
![EZ80L92AZ020SC00TR](/photos/6/76/67664/269-100-lqfp_tmb.jpg)
Part Number:
Description:
IC EZ80 MPU 100LQFP
Manufacturer:
Zilog
Datasheet:
![EZ80L92AZ050SC00TR](/photos/6/76/67664/269-100-lqfp_tmb.jpg)
Part Number:
Description:
IC EZ80 MPU 100LQFP
Manufacturer:
Zilog
Datasheet:
![EZ80L92AZ020EC00TR](/photos/6/76/67664/269-100-lqfp_tmb.jpg)
Part Number:
Description:
IC EZ80 MPU 100LQFP
Manufacturer:
Zilog
Datasheet:
![EZ80L92AZ050EC00TR](/photos/6/76/67664/269-100-lqfp_tmb.jpg)
Part Number:
Description:
IC EZ80 MPU 100LQFP
Manufacturer:
Zilog
Datasheet:
![EZ80190AZ050SC00TR](/photos/6/76/67664/269-100-lqfp_tmb.jpg)
Part Number:
Description:
IC EZ80 ACCLAIM 50MHZ 100LQFP
Manufacturer:
Zilog
Datasheet:
![EZ80190AZ050EC00TR](/photos/6/76/67664/269-100-lqfp_tmb.jpg)
Part Number:
Description:
IC EZ80 ACCLAIM 50MHZ 100LQFP
Manufacturer:
Zilog
Datasheet:
![EZ80L92AZ020SG](/photos/6/76/67664/269-100-lqfp_tmb.jpg)
Part Number:
Description:
IC WEBSERVER 20MHZ 100LQFP
Manufacturer:
Zilog
Datasheet:
![EZ80L92AZ050SG](/photos/6/76/67664/269-100-lqfp_tmb.jpg)
Part Number:
Description:
IC WEBSERVER 50MHZ 100LQFP
Manufacturer:
Zilog
Datasheet:
![EZ80190AZ050SG](/photos/6/76/67664/269-100-lqfp_tmb.jpg)
Part Number:
Description:
IC WEBSERVER 8 BIT 50MHZ 100LQFP
Manufacturer:
Zilog
Datasheet:
![EZ80L92AZ050EG](/photos/6/76/67664/269-100-lqfp_tmb.jpg)
Part Number:
Description:
IC WEBSERVER 50MHZ 100LQFP
Manufacturer:
Zilog
Datasheet:
![EZ80190AZ050EG](/photos/6/76/67664/269-100-lqfp_tmb.jpg)
Part Number:
Description:
IC WEBSERVER 50MHZ XTEMP 100LQFP
Manufacturer:
Zilog
Datasheet:
![EZ80L92AZ020EG](/photos/6/76/67664/269-100-lqfp_tmb.jpg)
Part Number:
Description:
IC WEBSERVER 20MHZ 100LQFP
Manufacturer:
Zilog
Datasheet:
![EZ80F93AZ020SG](/photos/6/76/67664/269-100-lqfp_tmb.jpg)
Part Number:
Description:
IC ACCLAIM MCU 64KB 100LQFP
Manufacturer:
Zilog
Datasheet:
![EZ80F93AZ020EG](/photos/6/76/67664/269-100-lqfp_tmb.jpg)
Part Number:
Description:
IC ACCLAIM MCU 64KB 100LQFP
Manufacturer:
Zilog
Datasheet: